Work out actual yield instantly with clear inputs, formula shown and shareable results.
Percent yield is the actual yield divided by the theoretical yield, so knowing any two of the three gives the third. Here the theoretical maximum is scaled by the yield achieved: a reaction with a 25 g ceiling running at 78% delivers 19.5 g of product and leaves 5.5 g unaccounted for.
Actual yield
actual = theoretical x percent yield / 100
Loss
loss = theoretical - actual
Incomplete reaction, competing side reactions, material left on glassware and losses during filtration or recrystallisation all reduce recovery.
Only as an error signal - usually residual solvent or an impure product. Genuine yields cannot beat the stoichiometric ceiling.